When Is Hit Wicket Out?

[woofas]

Watching a match the other day & it got me thinking about hit wicket:
a) Batsman plays a shot but treads on his wicket - obviously out.
b) Ball goes through to keeper who shies at the stumps, batsman is in but hits his own stumps - in or out?
c) Batsman runs but he collides with stumps at the bowler's end - I think in, but if they turn for another run what are the laws regarding a run out?

[FredPuli43]

http://www.lords.org/mcc/laws-of-cricket/laws/law-35-hit-wicket/

Read the above. The 'Not out, hit wicket' is more helpful than the first section.

[Buenchico]

"1. Out Hit wicket

(a) The striker is out Hit wicket if, after the bowler has entered his delivery stride and while the ball is in play, his wicket is put down either by the striker’s bat or by his person as described in Law 28.1(a)(ii), (iii) and (iv) (Wicket put down).

either (i) in the course of any action taken by him in preparing to receive or in receiving a delivery,

or (ii) in setting off for his first run immediately after playing or playing at the ball,

or (iii) if he makes no attempt to play the ball, in setting off for his first run, providing that in the opinion of the umpire this is immediately after he has had the opportunity of playing the ball,

or (iv) in lawfully making a second or further stroke for the purpose of guarding his wicket within the provisions of Law 34.3 (Ball lawfully struck more than once).

(b) If the striker puts his wicket down in any of the ways described in Law 28.1(a)(ii), (iii) and (iv) (Wicket put down) before the bowler has entered his delivery stride, either umpire shall call and signal Dead ball.

2. Not out Hit wicket

Notwithstanding 1 above, the striker is not out under this Law should his wicket be put down in any of the ways referred to in 1 above if,

(a) it occurs after he has completed any action in receiving the delivery, other than in 1(a)(ii), (iii) and (iv) above.

(b) it occurs when he is in the act of running, other than setting off immediately for his first run.

(c) it occurs when he is trying to avoid being run out or stumped.

(d) it occurs when he is trying to avoid a throw in at any time.

(e) the bowler after entering his delivery stride does not deliver the ball. In this case either umpire shall immediately call and signal Dead ball. See Law 23.4 (Umpire calling and signalling Dead ball).

(f) the delivery is a No ball."

http://www.lords.org/mcc/laws-of-cricket/laws/law-38-run-out/

So, in your example:
(a) Out
(b) Not Out
(c) Not Out

If the wicket has been broken (e.g. by the batsman colliding with the stumps as in your last example) with both bails removed then, in order to get a 'Run Out' decision, a fielder must either remake the wicket (replacing at least one bail) and then remove the bail in the usual manner or, far more likely, strike a standing stump (or pull it from the ground) with a hand holding the ball or with the arm attached to the hand holding the ball.

http://www.lords.org/mcc/laws-of-cricket/laws/law-28-the-wicket-is-down/

[Buenchico]

Oops. I put the wrong link (to Law 38 instead of Law 35) but Fred had beaten me to it anyway.

[FredPuli43]

I retire 'Not out', Buenchico, self-satisfied that, uniquely, for the first time I answered before you !